I decided to read Stoppard's play. I'm totally baffled. I don't feel that I obtained any insight into Shakespeare's play (or even know if I was supposed to get any such insight). I don't know what the two characters are about. Of course I "get it" -- they are weaving in and out of Shakespeare's Hamlet. It's about illusion and reality in a play. But I don't see why that's a good way to make that point.
Yesterday I watched the Beatles' movie "Hard Day's Night" which dates from the same era as this play and maybe asks some of the same questions. I like the Beatles' questions better. Who are you if you are onstage? Well, you aren't you and you are you. You can start giving silly answers to silly questions from your adoring public at cocktail parties. OK. I'm done.